Photographic material for producing dyestuff images



Patented Mar. s, 1937 PATIENT OFF-ICE PHOTOGRAPHIC MATERIAL FOR PRODUC-.

ING.D,YESTUFF WAGES Be'la Gaspar, Berlin, Germany No Drawing.

Application March 23, 1933, Serial No. 662,395. In Germany March 24,1932 {Claims This invention, rlat'es to photographic material forproducing dyestufl images, and more par,- ticularly positive images.

It is known in the production of dyestufl. images .5 to employ diffuselycolored recording or copying material.

In producing images, and more particularly reversed images, there areusually employed silver images. which are subsequently toned. The shadeswhichare obtained by toning or developing are limited in number and theproduction requires an appreciable length of time. 'It is also notalways possible to obtain the desired shade of color as a necessaryresult of the method em;-

The object of this invention resides in the production of dyestuflimages, which contain blackish or black dyestufis. In coloringphotographic material with dark or blackish colors, as necessary moreparticularly for the production of single-color or black-andwhitecolorimages, a'n extremely long time is required for the exposure.

Now it has been found that short-periods of exposure may be obtainedapproximately equal to those associated with normal photographicmaterials, if the material is sensitized in respect of infra-red rays.In addition to this, sensitization may also be performed in respect ofany 85 other gaps which may be present in the absorption range of thedyestuff.

Example 1 The dyestuflf Naphthylamine Black' 43(Schultz-Farbstofltabellen 1920 edition, ,page

405) is added to a silver halide emulsion. As

sensitizer there is added the dyestuflf Cryptocyanine. The emulsion thusprepared is poured on 45 to a desired backing or support (glass, film orpaper).

Example 2 Diamine Black BO (Schultz-Farbstofitabellen 0 1920 edition,page 405) isconverted by means of an organic base into an insoluble,non-difiusing salt, for example by conversion with cinchonine chloride,as described in my Patent No. 2,046,067 dated June 30, 1936. Thissubstance is then 55 added to a silver bromide layer.

to said invisible rays.

Ea'ample 3 I An insoluble dyestufl, such'as Sudan Black B, is dissolvedin alcohol or aceton, and added to the emulsion. Alternately the samemay also be admixed with the emulsion in powder form.

The exposed layers may be treated subsequently according to manydifferent processes. Thistreatment may consist, for example, inimmersing in a .bath containing means which destroy the dyestufi byoxidation or reduction at the points of the silver deposit or alsoatthepoints which are free of deposit, as described in my Patent No.2,020,775 dated November 12, 1935 and Patent No. 2,004,625 dated'June11, 1935. The subsequent treatment of the layers may also be performedwith the assistance of coupled reactions, such as have already beendescribed by Luther and von Holleben, or also by the use ofdyestuffdestroying agents in conjunction with images, which'have beenpreliminarily treated by mordanting or tanning. Beyond this it is alsopossible to produce in these layers wash-out reliefs by tanning andhardening and subsequent treatment in warm water. The images may beemployed for the production of direct positives, for I producingduplicate negatives, for the production of master images forphotomechanical purposes, for reproducing deed paper, etc. I

It will be understood that no limitation is made 30 to the specificexamples set forth in the above and that numerous modifications arequitepossible within the meaning of the above description and theannexed claims without departing from the spirit of the invention.

I claim:

1. Photographic material for the production of dyestufl imagescomprising a photographic colloid containing silver halide and dyed bymeans of a dyestuflf which is fast to said colloid, re- 40 sistant toordinary photographic treating baths and which absorbs substantially allof the visible rays of the spectrum but transmits invisible rays, and asensltizer sensitizing said colloid in respect 2. Photographic materialfor the production of dyestufi images comprising a photographic colloidcontaining silver halide and dyed by means of a dyestuff which is fastto said colloid resistant to ordinary photographic treating baths andwhich absorbs substantially all of the visible rays of the spectrum buttransmits infra-red rays and a sensitizer sensitizing said colloid forinfra-red rays.

3. Photographic material for the production of" dyestuif imagescomprising a silver halide emulsion dyed by means of Naphthylamine Black43 and a sensitizer sensitizing said emulsion in respect to infra-redrays.

4. Photographic material for the production of dyestuff imagescomprising a silver halide emulsion dyed with Diamine Black B0 and asensitizer sensitizing said emulsion in respect; to infra-red rays.

5. Photographic material for the production of dyestufi imagescomprising a silver halide emulsion dyed by means of Sudan Black B and asensitizer sensitizing said emulsion in respect to infrared rays.

6. Photographic material for the production of dyestuff imagescomprising a colloid containing silver halide and sensitized in respectto infrared rays by means of Cryptocyanlne 8, said colloid being dyedwith a dyestufl which is fast thereto and which absorbs substantiallythe whole of the visible rays of the spectrum, transmits infra-red, andis resistant to ordinary photographic treating baths.

7. Photographic material for the production of dyestufi imagescomprising a photographic colloid containing silver halide and dyed bymeans of a dyestufi which is fast to said colloid, resistant to ordinaryphotographic treating baths and which absorbs substantially all of thevisible rays ofthe spectrum, absorbing different of said visible lightrays in different degree but transmitting invisible rays and asensitizer sensitizing said colloid in respect to said invisible raysand those light rays for which the absorption of the dyestuif has aminimal value.

BELA GASPAR.

